I. Field of the Invention
The present invention relates generally to container handling equipment, including systems for accessing, grabbing, lifting and tipping a wide range of sizes and shapes of collection containers into charging hoppers or compartments of side loading collection vehicles, or other receptacles, and thereafter returning empty containers to their pickup locations. More particularly, the present invention relates to an automated container handling system including a container grabbing device, that is not only capable of lateral extension, but also capable of full lift and dump operation in very close quarters. A linearly-operating lift system is provided to lift and lower containers that cooperates with a pivoting, short-arm container grabbing device with hydraulic fingers. A rotary actuator pivots the grabbing device to adjust grabbing angle, tip containers and rotate it to and from a stowed position.
II. Related Art
Various vehicles dedicated to the collection of refuse or recyclables have included mechanized container handling devices that allow an operator to cause the device to access, lift, empty and return containers of interest without the need for any direct interaction by the operator so that the operator may remain in the vehicle. Such a holding or grabbing device is generally connected to an arm or extendable boom which is connected, in turn, to a base mounted on the vehicle. The arm or boom and grabbing device are operated in concert to access and engage a container of interest, lift and dump the container into a receiving hopper and return the empty container to the original location. One device of the class with an extensible boom is shown in U.S. Pat. No. 5,651,654 to Christenson and assigned to the same assignee as the present invention. Grabbing devices are also known which have opposed arms or fingers that converge around the girth of containers. Such devices generally have themselves been attached to extended arm members configured to pivot in a generally vertical plane to lift and invert a captured container and return it empty to an upright position. One such container grabbing device is illustrated and described in U.S. Pat. No. 5,769,592 to Christenson and also assigned to the same assignee as the present invention.
Systems also have been devised in which converging/diverging gripper arms are mounted on a carriage to reciprocate along a lift assembly using a chain drive or another mechanism. Such systems are disclosed in U.S. Pat. No. 5,230,393 and RE34,292. Another device is shown in U.S. Pat. No. 5,702,225 which depicts a pivoting linear lifting system operable along a pair of spaced rails. Curves in upper portions of the rails determine and control the tipping angle and radius for a captured container.
Mechanisms of known container handling devices generally have a large number of moving parts and articulated joints which are exposed to the extreme clogging and corrosive conditions of refuse collection, and, as such, tend to require frequent maintenance. It would thus be advantageous to provide a simplified mechanism to automatically operate the lift and dump arm function that reduces mechanism complexity and maintenance requirements. There is also a need to reduce the required lateral and/or vertical distance necessary for operation of such a lift and dump system so that an associated collection vehicle can successfully automate collection in narrower passages such as alleyways, or the like, in addition to emptying curb-side containers on wider streets.